Part 5, 1916] AGARICACEAE 297 
27. LENTODIELLUM Murrill, Mycologia 7: 216. 1915. 
Persistent, fleshy-tough, densely cespitose; piles smooth, deeply depressed: lamellae 
decurrent: spores hyaline: veil scanty, evanescent: stipe central, hard, woody. 
Type species, Panus concavus Berk. 
1. Lentodiellum concavum (Berk.) Murrill, Mycologia 7: 216. 1915. 
Ponus concavus Berk. Ann. Mag. Nat. Hist. IT. 9: 194. 1852. 
? Lentinus cochleatus occidentalis Fries, Nova Acta Soc. Sci. Upsal. IIY. 1: 227. 1855. 
Pileus tough but fleshy, infundibuliform, densely cespitose, 3-8 em. broad; surface glabrous 
but not polished, chalky-white, not striate, margin strongly incurved, appendiculate: lamellae 
strongly decurrent, crowded, narrow, white becoming yellowish: spores oblong-ellipsoid, 
pointed at one end, smooth, hyaline, 6-7  2.5-3 u: stipe exannulate, central or nearly so, 
cylindric, connate below, glabrous or subglabrous, white, solid, tough, 4-8 cm. long, 3-4 mm. 
thick: veil thick, white, appendictulate. 
TYPE LOCALITY: Santo Domingo. 
Hasrrat: On dead logs and stumps. 
DISTRIBUTION: Tropical America. 
Subtribe 1. LEPIOTANAE* 
Hymenophore fleshy or membranous, not reviving. 
Stipe eccentric, lateral, or wanting; pileus irregular. 
Pileus not distinctly stipitate, sessile or contracted into a stipe-like 
base, often resupinate when young. 28, GEOPETALUM. 
Pileus distinctly stipitate, the stipe either eccentric or lateral, and 
sometimes much reduced. 
Lamellae conspicuously decurrent; stipe eccentric or lateral. 29, CREPIDOPUS. 
Lamellae adnate or sinuate; stipe ‘usually eccentric. 30. MICROMPHALE. 
Stipe central; pileus regular. 
Stipe slender, tubular, with a cartilaginous cortex. 
Margin of pileus at first straight and appressed to the stipe. 
Pileus plicate, splitting down the backs of the lamellae. - 31. Lepromyces. 
Pileus even or striate, not splitting. 
Pileus usually umbilicate; lamellae decurrent. 32, OMPHALOPSIS, 
Pileus usually convex, often umbonate; lamellae adnate or 
adnexed. 
Stipe and lamellae lactiferous, bleeding when cut. 33, GALACTOPUS. 
Stipe and lamellae not lactiferous. 34. PRUNULUS. 
Margin of pileus at first incurved. 
Lamellae decurrent; pileus usually umbilicate. 35. OMPHALINA. 
Lamellae adnate or adnexed. 36. GyMNOPUS. 
Stipe stout, fleshy, of uniform texture. 
‘Lamellae waxy at maturity. 
Veil absent; pileus often bright-colored. 
Pileus viscid, usually fragile and bright-colored. 37. Hyprocvse. 
Pileus not viscid, usually firm and without brilliant colors. 38. CamMaROPHYLLUS. 
Veil present, glutinous, forming an annulus or reduced to 
squamules; pileus not bright-colored. 39. HyGROPHORUS. 
Lamellae fleshy, not waxy. 
Volva and veil absent, the latter sometimes rudimentary. 
Lamellae decurrent or adnate. 
Spores not conspicuously verruculose or echinulate, 
usually ellipsoid; lamellae decurrent or adnate. 
Hymenophore usually solitary or gregarious, sub- 
cespitose to cespitose but not wood-loving in C. 
muliceps and a few other species. 40. CLiTocyvBE. 
Hymenophore densely cespitose and wood-loving, 
attached to decayed trunks or roots. 41, MonapEeLpuus. 
Spores conspicuously verruculose or echinulate, glo- ~~ 
bose; lamellae adnate. 42. LACCARIA, 
Lamellae sinuate; spores usually ellipsoid and smooth. 
Pileus smooth or inconspicuously decorated with fibrils 
or scales, 43. MELANOLEUCA. 
Pileus conspicuously decorated with fibrils or scales. 44, CorTINELLUS. 
Volva absent, veil present, usually forming an annulus, : 
Stipe eccentric. 45. PLEUROTUS. 
Stipe central. 
Lamellae adnate or adnezed. 46. ARMILLARIA. 
Lamellae free, varying at times to adnexed or adnate. 
* The first part of the key to this subtribe, containing species with the hymenophore tough to 
woody, reviving, appears on page 237 of this volume. 
